If you make it a ratio, it will be 12:6 which is reduced to 2:1.
The graph opens downward, so the vertex is the maximum point of the parabola. Example: The vertex of the parabola y = -(x + 9)2 + 4 is (-9, 4). The graph opens downward, so the vertex is the maximum point of the parabola.
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If the value of "a" is positive, the parabola will open upward.
Answer:

Step-by-step explanation:
If we have that worded expression, we can convert it into actual mathematical terms.
x to the one sixth power: 
That to the power of 3:

Using exponent rules, since we have a power to a power, the powers multiply, so:

If we have a number to a fraction power, the denominator becomes the “find the (denominator) root of x.
So:

Hope this helped!
Range should be (-∞ , 10]
answer is C.